Cleaning appliances such as vacuum cleaners are well known. The majority of vacuum cleaners are either of the “upright” type or of the “cylinder” type (called canister or barrel machines in some countries). Cylinder vacuum cleaners generally comprise a main body which contains a motor-driven fan unit for drawing a dirt-bearing air flow into the vacuum cleaner, and separating apparatus, such as a cyclonic separator or a bag, for separating dirt and dust from the air flow. The dirt-bearing air flow is introduced to the main body through a suction hose and wand assembly which is connected to the main body. The main body of the vacuum cleaner is dragged along by the hose as a user moves around a room. A cleaning tool is attached to the remote end of the hose and wand assembly.
For example, WO 03/068042 describes a cylinder vacuum cleaner having a chassis which supports cyclonic separating apparatus. The vacuum cleaner has two main wheels, one on each side of a rear portion of the chassis, and a castor wheel located beneath the front portion of the chassis which allow the vacuum cleaner to be dragged across a surface. Such a castor wheel tends be mounted on a circular support which is, in turn, rotatably mounted on the chassis to allow the castor wheel to swivel in response to a change in the direction in which the vacuum cleaner is dragged over the surface. The separating apparatus comprises an air inlet through which air can enter the separating apparatus in a tangential manner, and an air outlet which is located on a rear wall of the separating apparatus for conveying air to a fan unit for drawing an air flow through the vacuum cleaner.
PCT/GB2010/050418 describes a cylinder vacuum cleaner having a generally spherical rolling assembly connected to the chassis for improving the maneuverability of the vacuum cleaner over a floor surface. The rolling assembly comprises a body and a pair of dome shaped wheels connected to the body. The chassis extends forwardly from the body of the rolling assembly, and includes a pair of wheels for steering the vacuum cleaner and for supporting the rolling assembly as the vacuum cleaner is maneuvered over a floor surface.
The chassis also includes a support for supporting cyclonic separating apparatus of the vacuum cleaner. The support is located on an inlet duct for conveying a dirt-bearing air flow to the separating apparatus. To assist with the maneuvering of the vacuum cleaner around objects located on the floor surface, the inlet duct is pivotably connected to the chassis for movement relative to the chassis as the user pulls the vacuum cleaner in different directions over the floor surface. The movement of the duct relative to the chassis actuates a steering mechanism for turning the wheels connected to the chassis. The inlet duct comprises a relatively rigid section connected to the chassis for pivoting movement relative thereto, and a relatively flexible hose located upstream to the rigid section and which tends to flex relative to the rigid section as the duct pivots relative to the chassis.